1. Field of the Invention
This invention relates to an alarm system for bicycles and the like, and more particularly to an alarm system which is actuated by movement of the bicycle.
2. Description of the Prior Art
Various systems have been proposed in the past for actuating an alarm on a bicycle or similar vehicle to prevent its being stolen or tampered with. Several of these systems provide an audible alarm as an adjunct of a bicycle lock. For example, in U.S. Pat. No. 3,866,205 to Payne et al a gas-filled cylinder is mounted on a bicycle with a gas tube that can be wound around a support and locked back on the cylinder, thus locking the bicycle to the support. If the tube is cut the decrease in pressure within the cylinder actuates an alarm. Another system using the same general approach of a combination lock and alarm is disclosed in U.S. Pat. No. 3,824,540 to Smith. In this patent a cable is wound through the bicycle wheels and the frame to immobilize the wheels. An electrical conductor runs through the length of the cable and activates an alarm when it is cut. A similar approach is taken in U.S. Pat. No. 3,791,861 to Adler, in which a cable is used to lock a bicycle to a support. Cutting the cable interrupts an electrical connection and causes the alarm to be sounded.
A different device that actuates an alarm without the use of a locking system is disclosed in U.S. Pat. No. 550,229 to McDonald et al. In this patent metal tape is wrapped around the opposite gripping ends of the handlebars. Pressure sensitive switches under the tape are connected with a battery and bell circuit such that touching one or the other of the handles causes a bell to ring. If both handles are gripped at the same time an electrical shock is administered.
While each of the above systems is designed to operate an alarm if an attempt is made to steal or otherwise remove a bicycle, there is still a need for a simple alarm system that is activated whenever a bicycle is moved, and which does not injure the person moving it. It would also be desirable for such a system to be inexpensive, to not interfere with the normal operation of the bicycle, and to not require any extraneous equipment to carry such as chains or cables.